Α‐fetoprotein Levels in Normal Males From Seven Ethnic Groups With Different Hepatocellular Carcinoma Risks

Abstract

Alpha-Fetoprotein (AFP) levels of 1,335 males (15 years and older) of seven ethnic groups (Chinese, Indians, and Malays from Singapore, Caucasians from Lyon, and Blacks from Nairobi, forest, and the savanna region of the Ivory Coast) were determined by radioimmunoassay. A few elevated levels (up to 30 nanounits/ml) were detected in some normal individuals, especially in the older age-groups. In addition, there was a systematic age-dependency of AFP levels particularly evident in the groups from Singapore-Lyon, in which there was a 50% AFP increase between the ages of 20 and 40. Comparison between Africans on the one hand and people from Singapore-Lyon on the other hand revealed highly significant differences (p less than 0.001), especially in the younger groups, whereas Chinese, Malays, and Indians from Singapore had very similar AFP pattern; this suggests an important role for environmental factors in the regulation of AFP levels. The age dependency of the presumed effect of environmental factors is in keeping with experimental data showing that young animals respond more vigorously to AFP-stimulating factors. Although the incidence of hepatocellular carcinoma (HCC) differs in the three Singapore groups (the highest in Chinese and the lowest in Indians), no relationship was observed in this study between mean AFP level and HCC incidence in Singapore.

M2 alpha-1-antitrypsin phenotype and primary liver cancer

“…One of those forms, the MZ phenotype, has been found by Clerc et al (1977) to be a risk factor for PLC, whereas others, such as Charlionet et al (1976) and Beaugrand et al (1978), have not found such an association. In the latter group, one can also include Theodoropoulos et al (1976) who, on the other hand, found a positive correlation between "FM" (fast moving) (xi-AT components and PLC.…”

Mean α-Fetoprotein Values of 1,333 Males over 15 Years by Age Groups

“…Although highly significant, the low value of the coefficient of correlation (r = 0.3095) seems to indicate that the AFP-age relationship is not strong and can be easily modified by a number of factors. It may be that there were small clinically undiagnosed or undiagnosable pathological alterations of the liver either due to infections or parasitic diseases or to toxic aggressions, especially in the older age groups; in this study however a group of Africans from the Ivory Coast, who were chronically infected with hepatitis B virus, did not show higher AFP levels than the negative controls (29). In each ethnic group there was a tendency for AFP to increase with age and pooling all groups together smoothed the curve.…”

“…1) as well as purified AFP and individual normal sera (29). Dilutions of the standard down to 0.25 IU/ml1 gave percent inhibition regularly located on 1 By definition (31) 1 IU of AFP is the amount of AFP which is present in 1.3991 Mg of the lyophilized cord serum preparation constituting the international standard and is equal to 1 (former) nIU (29). When examined by 11 laboratories (30) 1 (present) 1U was found to be worth from 0.54 to 1.81 ng of AFP.…”

“…Details on the age distribution as well as on technical aspects of the RIA were previously reported (29). It is sufficient here to recall that 847 individuals (from Lyon, Nairobi and Singapore) were blood donors, whereas the remaining males were bled from randomly selected villages.…”

Alpha‐fetoprotein

“…However, the significance of this observation in regard to the presence of racial differences, hepatocarcinogen exposure, or endemic hepatitis remains unclear. After a systematic survey of males from seven populations at apparent different risk for hepatoma development, no conclusive demonstration of an association of elevated AFP concentrations was found, although a slight increase with age was noted [170]. Another study [90] noted a small decrease in the average serum AFP concentration after 60 years of age.…”